Laboratory Treatments for Suppression of Southern Red Mite, 1996

In response to cancellation of Omite (propargite) as the only short-term control for this pest mite on cranberries in 1996, we evaluated seven compounds to determine which warranted further field testing. Forty sweet pepperbush (Clethra alnifolia) leaves were ‘cleaned’ of existing debris using a paper towel wetted with distilled water. Each pepperbush leaf was then placed singly in a petri dish that contained three sheets of filter paper saturated with distilled water to prevent both mite escape and leaf desiccation. Each treatment and the check (water) had 5 replicates. Applications were made with a hand sprayer. Ten adult mites were placed on each pepperbush leaf and were sprayed with a test material to runoff. Covers were then placed on the petri dishes to reduce evaporation. The bioassay plates were placed in a growth chamber at 25& C, with 14:10 LD. Each treatment and check was evaluated for living and dead mites at 1, 3 or 4, and 7 days after treat-ment.